main-man why do you carry guns. for protection? because they arent much use for protection unless you know beforehand that somebody is going to attack you in which case you may as well call the police.
if you dont know someones going to attack you and they suddenly jump out with a gun pointed to ur head theres not much you can do because if u reach for ur gun theyll shhot you. it doesnt work.
also its inevitable that if everyones carrying guns with them then certain people are going to use them for bad and as shown earlier theyre pretty much useless for protection so only bad can come from them.